Coated abrasive implement



Jan. 26, 1965 R. S. MANCHESTER U COATED ABRASIVE IMPLEMENT AW /4- A /4 Filed March 29, 1963 INVENTQR. v [PANDA LL 8. Mmvcnzsrze A T To IENEY United States Patent Ofifice 3,16%,8Y6 Patented Jan. 265, 1965 3,166,376 COATED ABRASIVE IMPLEMENT Randall S. Manchester, North Troy, NFL, assignor to Norton Company, Troy, N.Y., a corporation of Massachusetts Filed Mar. 29, 1963, Ser. No. 269,035 7 Ciaims. (Cl. 51-375) The present invention relates to a coated abrasive construction adapted to be formed into a variety of abrading or polishing implements, to the coated abrasive implements so formed, and to the method of forming such coated abrasive implements.

Heretofore, many types of abrading or polishing devices have been formed from coated abrasives, including wheels, rolls, pencils, bands, discs and the like. Most of these are formed for a specific purpose such as to engage and polish or abrade a specific contour, to deburr a given diameter opening or the like.

The present object hasfor its principal purpose the provision of a coated abrasive implement capable of performing a variety of operations including conforming to varying contours and adjusting to various diameter openlugs for deburring purposes.

Another object of the invention is to provide a basic coated abrasive construction capable of being formed into a variety of implements as desired.

Additional objects, if not specifically set forth herein, will be readily apparent to one skilled in the art from the following detailed description of the invention:

In the drawings:

FIGURE 1 is a diagrammatic illustration of the present invention showing certain limits essential to the effective operation thereof.

FIGURE 2 is a plan View of a strip of coated abrasive material prepared according to the present invention.

FIGURE 3 is a perspective view of a coated abrasive implement made from the strip illustrated in FIGURE 2.

FIGURE 4 is a perspective view of another type of implement made from a similar strip of coated abrasive material to that shown in FIGURE 2.

FIGURE 5 is a perspective view of the device of FIG- URE 3 as it appears when rotated at high speeds.

Generally, the present invention comprises providing a strip of coated abrasive material having a plurality of transverse slots provided in its surface, said slots being of a particular configuration and spacing as hereinafter described in detail.

More specifically, referring to FIGURE 2 of the drawings, the strip 20 of coated abrasive material is provided with a series of arcuate cuts or slots 21 extending trans versely across the strip 20 terminating short of the edges 22 of the strip and extending entirely through the back ing material 23 and coating 24 thereof. These slots are prepared by using a punch-type die or by other suitable means and must conform to certain limitations as illustrated diagrammatically in FIGURE 1.

Referring now to FIGURES 1 and 2, line 163 represents a transverse line normal to the edges 11 of a given rectangular strip of coated abrasive material such as that illustrated at 20 in FIGURE 2. The slots or cuts which may be made in the coated abrasive strip in accordance with the present invention are represented by the reference letters A-A', BB' and C-C' respectively. Line 12 is the portion of the radius of the circle formed by the arcuate slot or out A, B or C subtended by the transverse line or chord It). This is conventionally referred to as the rise. Two sets of identical curves A and A are shown and it will be noted that ends 13 of curve A are at substantially the same distance d from the edges 11 of the coated abrasive strip as are the ends 14 of curve A. Dotted line R indicates the distance between the ends of the curves A and A in a direction parallel to the rise of the curve. In anyv given abrasive section embodying this invention, the distance R will be the same between adjacent slots. The limits of the arcuate curves can be defined in terms of the relationship of the rise of the curve to the distance R between the ends of the curves, since for any given abrasive strip the curves will be parallel. The illustration described above with curves A-A' is the optimum, i.e. the rise is equal to the distance R between the ends of the arcs. Curve B illustrates the minimum permissible curvature wherein the rise is equal to /3R, while curve C illustrates the maximum, curvature wherein the rise is equal to three times the distanceR. In each of these latter instances, the companion curve B or C has its ends spaced the distance R from'the corresponding ends of curve B or C.

For any given coated abrasive strip, the arcuate slots will be substantially identical within the limits of the dies used and the material being died out. The distance between the ends of the slots (R in FIGURE 1) may be varied as desired but will be the same between each slot in a given strip once the desired distance is selected. Likewise the spacing at the edge of the strip (distance d inFIGURE 1) may be varied as desired depending upon the end use to which the implement formed from the strip is to be put, but once selected will remain substantially the same for all slots of the given strip. Since one of the requirements of any of the arcuate slots used in this invention is that it have a rise less than the radius of the circle of which the arc is a part, the formula that the rise be within the range of from /3 to 3 times the distance between the ends of adjacent arcuate slots gives a fixed limitation to the types of curves which may be satisfactorily employed.

The strip prepared by dieing out the slots as described above may then be made into any one of a variety of forms. In all instances, at least one convolution of material is formed with the ends of the strip being fastened-preferably to the material itself by an adhesive-but if desired to the surface of the drum or mandrel to be used to rotate the device. Referring now to FIG- URES 3 and 4, two types of implements are shown. In FIGURE 3, the strip of coated abrasive material having the slashes or slots 31 therein as described above is shown with a plurality of convolutions adhesively secured one to the other along the unslashed edges 32 and 33 to form a cylinder mounted upon a mandrel 34 adapted for use with a rotary drill or the like (not shown). It will be noted that the slashed segments '35 of the device stand out at an angle from the general plane of the circumference of the cylinder formed by edges 32 and 33 and gradually increasing the diameter of such cylinder to a maximum at the'center, with the convex portion 36 of each segment at a higher elevation than the interior concave portion 37. The device is rotated in the direction shown by the arrow so that the lower edge 37 of each segment 35 approaches the workpiece first with the portion of segment 35 towards edge 36 then abrading as it passes over the piece. There is no danger of catching a leading edge 37 of the segments 35 with this construction, and as one segment layer wears away, the segments will break off exposing the next layer. FIGURE 4 shows a device wherein only several convolutions of abrasive strip material 40 are used. Again the edges 41 and 42 adjacent the curved segments 43 formed by slashes 44 are adhesively secured to the next adjacent convolution. In this instance the band formed by the convoluted strip 4% is mounted on an expandable rubber mandrel 45 which is adapted to be rotated by a suitable power source (not shown). As indicated, the slashed strip may form one or many convolutions with the requirement that the curved segments -themse1ves remain free while the unslased edges tearing of segments 35. tensionot'the segments 35 can be controlled by fixing thefree end'33 of the device at the desired degree of san ers D as are

secured.

In operation, centrifugal force will tend to force the f slasheszto extend from the plane of the cylinder formed .by 'the securedsunslashed ends of the convoluted strip as i isashownrinFIGURE 5. .Here the device illustrated in FIGURE 3 is shown as it would appear if being rotated iat high speed. The segments 35 extend outwardly to ."form a narrow band at the center of the stripthe cyl- *inder formed by edges '33 of the strip being free to slide upon mandrel'34 with the other end of the device 32 being secured by threadedportion 38 of the mandrel 34.

. .Again, it will-be noted that the convex edge 36 of each segment '35 remains at a higher elevation than the concave edge 3'7 thus permitting abradingwithout snagging or If desired, the degree of exexpansion. This can be done permanently with the use of appropriate mandrels or temporarily by use of tape,

v :threaded:rnandrels with an adjusting nut or by such other means as may be desired.

Thedevices formed by the present invention not only use'as a replacement'for pencils and bands heretofore used inthe coated abrasive art, but also replace to-some extent coated abrasive flap wheels. In the flap 'wheeL'much-of the abrading is done by the edge of the "abrasive sheet. "With the device of the present invention,

due to the lesser diameter of the leading edge of abra- -3 sive, the abrading is done by the 'width of the face of the segment rather than the edge. This broader area of abrading contact provides a much more effective device for 1 manyapplications.

=The coatedabrasive strip may be Wound either clockwise or counter-clockwise to form the cylinders of the devices of'the present invention.

In all instances the cylinders have rigid or semi-rigid ends with the center --por-tion (containing the arcuate sections) capable of a wide variation of shape. A's-the ends of the cylinder are "*moved closer towards one another either deliberately or through-the action of centrifugal force, the cylinder will develop a bell-shaped profile as can be seen from FIG- URE 5 of the drawings. This permits rapid and accurate contouring with these devices and provides an adaptability heretofore not available from prior art abrading devices.

WhiIe the ends of the cylinders illustrated are shown as adhesively secured to the next adjacent convolution, a piece of adhesive tape, a metal clamp or other securing device can be used for this function if desired.

Obviously, many variations and modifications may be made Without departing from the spirit and scope of the invention disclosedherein'and therefore only such limita- ="tions should be imposed as are contained in the appended claims.

- strip of coated abrasive material having a flexible backing and a plurality of abrasive grains adhesively bonded to one surface thereof wherein a plurality of arcuate slashes are provided in the strip extending entirely through said backing and said coating, said arcuate slashes being substantially parallel to one another and extending in a row along the length direction of said rectangular strip.

2. A coated abrasive article comprising a rectangular strip of a flexible backing having a coating of a plurality of abrasive grains adhesively bonded to one surface there of; a continuous, unbroken edge section of said backing and said coating extending along each of the long sides of said rectangular strip; and a plurality of substantially parallel, spaced arcuate slashes disposed between said unbroken edge sections, each of said slashes extending from one unbroken edge section to the other and penetrating entirely through said backing and said coating between said unbroken edge sections.

3. An article as in claim 2 wherein the distance between adjacent arcuate slashes at the point where such slashes meet said unbroken edge section ranges from one-third to three times the length of the rise of the are formed by said arcuate slashes.

4. A coated abrasive implement comprising a band formed from at least one convolution of a coated abrasive strip as in claim 2, wherein said strip is wound with its abrasive coated surface outward and the unbroken edge sections are secured against unwinding.

5; A coated abrasive implement comprising a cylinder of coated abrasive material formed by winding a rectangular strip of coated abrasive material, abrasive surface out; an unbroken edge section of coated abrasive material extending along each end of said cylinder, said edge section being secured against unwinding; and a plurality of arcuate sections of said coated abrasive material formed integrally with and attached only to said edge sections, said arcuate sections extending be tween said edge sections and being free of connection with adjacent arcuate sections along the arcuate lines defining said sections.

6. An implement as in claim 5 wherein the distance between the ends of adjacent arcuate lines defining said arcuate sections ranges from one-third to three times the length of the rise of said arcuate lines.

7. A coated abrasive implement comprising a cylinder of coated abrasive material having an unbroken edge section extending along each end thereof; and a plurality of arcuate segments integrally formed from said coated abrasive material, said segments projecting from the surface of said cylinder at an angle and increasing the diameter of said cylinder towards the center thereof.

References Cited by the Examiner UNITED STATES PATENTS 2,199,906 3/38 Lippett 5ll90 2,938,309 5/60 Poilett 51-191 LESTER M. SWINGLE, Primary Examiner. 

7. A COATED ABRASIVE IMPLEMENT COMPRISING A CYLINDER OF COATED ABRASIVE MATERIAL HAVING AN UNBROKEN EDGE SECTION EXTENDING ALONG EACH END THEREOF; AND A PLURALITY OF ARCUATE SEGMENTS INTEGRALLY FORMED FROM SAID COATED ABRASIVE MATERIAL, SAID SEGMENTS PROJECTING FROM THE SURFACE OF SAID CYLINDER AT AN ANGLE AND INCREASING THE DIAMETER OF SAID CYLINDER TOWARDS THE CENTER THEREOF. 